But RadarOnline reports that the former Disney star did not return from a judges break about 9pm and although her seat was empty, the rest of the gang carried on without her.

'All the judges took a break together but when Britney, Simon and L.A. came back there was no sign of Demi,' a source told the site. 'They just carried on taping without her.'

'It was a bit weird and everyone wondered where she'd gone.'

This is not the first time that judges have done disappearing acts from set. Britney missed an audition in Kansas and 'took a break' missing three auditions during her first day in Texas.

'If someone needs a restroom break, of course the other judges just continue,' an insider said adding that Demi later returned. 'There's a lot of auditions to get done every day and they don't finish until 10 or 11pm as it is. It's no big deal.'